Characterizations in a random record model with a non-identically distributed initial record

We consider a sequence of random length M of independent absolutely continuous observations Xi, 1 = i = M, where M is geometric, X1 has cdf G, and Xi, i = 2, have cdf F. Let N be the number of upper records and Rn, n = 1, be the nth record value. We show that N is free of F if and only if G(x) = G0(F (x)) for some cdf G0 and that if E (|X2|) is finite so is E |Rn|) for n = 2 whenever N = n or N = n. We prove that the distribution of N along with appropriately chosen subsequences of E(Rn) characterize F and G, and along with subsequences of E Rn - Rn-1) characterize F and G up to a common location shift. We discuss some applications to the identification of the wage offer distribution in job search models.Wages ; Labor mobility

Identification of search models with initial condition problems

This paper extends previous work on the identification of search models in which observed worker productivity is imperfectly observed. In particular, it establishes that these models remain identified even when employment histories are left-censored (i.e. we do not get to follow workers from their initial job out of unemployment), as well as when workers set different reservation wages from one another. We further show that allowing for heterogeneity in reservation can affect the empirical estimates we obtain, specifically estimates of the rate at which workers receive job offers.Labor mobility ; Wages

Roto-translated Local Coordinate Frames For Interacting Dynamical Systems

Modelling interactions is critical in learning complex dynamical systems, namely systems of interacting objects with highly non-linear and time-dependent behaviour. A large class of such systems can be formalized as $\textit{geometric graphs}$, $\textit{i.e.}$, graphs with nodes positioned in the Euclidean space given an $\textit{arbitrarily}$ chosen global coordinate system, for instance vehicles in a traffic scene. Notwithstanding the arbitrary global coordinate system, the governing dynamics of the respective dynamical systems are invariant to rotations and translations, also known as $\textit{Galilean invariance}$. As ignoring these invariances leads to worse generalization, in this work we propose local coordinate frames per node-object to induce roto-translation invariance to the geometric graph of the interacting dynamical system. Further, the local coordinate frames allow for a natural definition of anisotropic filtering in graph neural networks. Experiments in traffic scenes, 3D motion capture, and colliding particles demonstrate that the proposed approach comfortably outperforms the recent state-of-the-art.Comment: NeurIPS 202

Effect of Parasitic Elements on the Performance of Buck-Boost Converter for PV Systems

In the proposed study, MOSFET device used in buck-boost converter for PV systems is studied. The parameter of MOSFET Rds(on) is varied and its effect on output voltage is studied. The parasitic elements in inductor and capacitor such as resistance on buck-boost converter performance are studied.  From the proposed study it has been found that the effect of parasitic resistance in capacitor is less as compared to parasitic resistance effect of inductor. Also the proposed study gives better insight into parasitic effect of Printed Circuit Board and losses incurred due to the same. In PV systems buck-boost converter is used to convert solar energy to electrical energy which is then stored in battery to drive the loads. These parasitic elements will have considerable effect on the performance of buck-boost converter such as efficiency and output voltage as validated by experimental results.DOI:http://dx.doi.org/10.11591/ijece.v4i6.685

Spacings around and order statistic

We determine the joint limiting distribution of adjacent spacings around a central, intermediate, or an extreme order statistic Xk:n of a random sample of size n from a continuous distribution F. For central and intermediate cases, normalized spacings in the left and right neighborhoods are asymptotically i.i.d. exponential random variables. The associated independent Poisson arrival processes are independent of Xk:n. For an extreme Xk:n, the asymptotic independence property of spacings fails for F in the domain of attraction of Fréchet and Weibull (α≠1) distributions. This work also provides additional insight into the limiting distribution for the number of observations around Xk:n for all three cases

GREEN SYNTHESIS OF PYRAZOLO [3,4]-PYRIMIDINE-THIONES USING IONIC LIQUID 2-METHYL-IMIDAZOLIUM-OXALATE AS POTENT EHRLICH ASCITES CARCINOMA RECEPTOR ANTAGONISTS

Objective: Pyrazolopyrimidines are heterocyclic molecules containing nitrogen as the main composition, and hence, they exhibit pharmacological efficacy. They are analogs of purines so that possessing wide applications in the field of medicinal chemistry. The main objective of this study is to synthesize different derivatives of pyrazole-pyrimidine classes by adopting simple methodology as well as by employing green chemistry. The purpose of the synthesis of these molecules is to study the antitumor activity against Ehrlich ascites carcinoma (EAC) cell lines. Methods: After literature studies, it makes us to involve in the research of synthetic organic chemistry, especially to synthesize new compounds of pyrazolopyrimidines. We are reported solvent-free synthesis of pyrazolo [3,4-d]-pyrimidine-thiones through ethyl acetoacetate, hydrazine hydrate, thiourea, and different benzaldehydes. An ionic liquid 2-methyl-imidazolium-oxalate catalyzed the reactions under ultrasonication bath. Both conventional and ultrasonic methods were employed and comparison studies have been made. It was found that ultrasonic method completed the reaction quicker than the conventional method. All the synthesized compounds were confirmed their structures by 1HNMR, Fourier transform infrared, 13C-NMR, and elemental analysis spectra. The compounds were tested for in vitro anticancer activity against EAC cell lines. Most compounds revealed significant anticancer activity relative to doxorubicin as a positive control with inhibitory concentration (IC50) values. Results: Ultrasonication method is a simple method under which all the reactions were completed at faster time (<7 min) compared to the convention method. Among eight molecules, 8a and 8d completed the reactions at a faster rate. We reported IC50 values of all the molecules, in which 8e and 8g were exhibited excellent potency against EAC cell lines at different concentrations . Conclusions: Ultrasonication method is an excellent method for the organic synthesis. We are herein reported that under this method, all the reactions are completed within 7 min. Hence, it is superior method than the conventional method. All synthesized molecules have shown good inhibitor potency against EAC cell lines. Among them, two molecules 8e and 8g have shown excellent inhibitor potency